Heat exchanger of the plate-pile type



May 7, 1957 G C. EG ENWALL HEAT EXCHANGER OF THE PLATE-FILE TYPE FiledJune 2, 1955 lam]. 3 x 1 v my. a

, IINVENTCYJR 0-105 TA F Co/v/v 0 EGf/V WA LIL ATTORNEY llite HEATEXCHANGER UP THE PLATE-FILE TYPE Gustaf Conrad Egenwall, Stockholm,Sweden, assignor to Aktieholaget Rosenhlads Patenter, Stockholm, SwedenThe present invention relates to heat exchangers of the so-ealledplate-pile type comprising heat transferring plates of thin-gage sheetmetal individually suspended from a carrier bar extending transverselyto the lateral faces of the plates, by means of catche individuallyprovided one for each plate and extending across the upper portion ofthe carrier bar, the two ends of each of said catch being attached tothe corresponding plate on both sides of the bar.

It is common practice, in such apparatus, to arrange the plates so thatthey may be separated by being displaced along the carrier bar to enabletheir lateral faces to be cleaned when in situ, and also so that theplates may be removed individually from the carrier bar. In order toprovide for the latter possibility, the attachment of the catch to theplate will have to be releasable in some way or other. it is true thatseveral arrangements to this effect have been proposed in the past butas a rule, these known arrangements leave a great deal to be desired invarious respects. Thus, for instance, they may be attained only as aresult of a comparatively costly special construction of the catchproper and/or of the plate. On the other hand, plate attachments whichfor their safe retentive action depend on the gravity loading from theplate proper and which are releasable in conjunction with a slightlifting movement of the plate, may tend to be released inadvertently,for instance when, after having been moved apart, the plates aresubjected to cleaning action by being scrubbed, or for some other reasonthey are subject to vibrations r shocks so that the plates may drop outand get damaged.

Plate attachments of the known types being releasable only by usingtools and/or possibly being of multi-part construction, are not readilyhandled.

This invention has for its object to avoid all the inconveniences anddrawbacks now referred to and to provide a novel plate attachmentconstruction which combines all advantages inherent in a simple andcheap method of production, full safety against inadvertent release ofthe attachment, an easy and convenient releasability of the plate fromits carrier bar without the use of tools and without the necessity ofremoving the catch or any other part from the plate. However, the catchmay be removed from the plate if desired.

For the objects stated, the invention is mainly characterized in thatthe catch is provided at both its ends with two resiliently separablelegs of thin-gage sheet metal adapted to grip an adjacent edge portionof the plate between their opposed fiat faces, each catch end beingadapted to be positively engaged with the plate in a manner only to bereleasable therefrom by resiliently spreading said legs apart.

The invention will now be described more in detail, reference being hadto the accompanying drawing illustrating, by way of example only, a fewembodiments thereof, and in which:

Fig. l is a lateral elevation, partly in cross-section and tatfis Patentpartly fragmentary, of a portion of the top part of a heat exchangingplate with a suspension attachment according to the present invention.

Fig. 2 shows the arrangement of Fig. 1 in a horizontal section takenalong the line Illl in this figure.

Fig. 3 shows the same arrangement in the same section but with theattachment in a position for enabling removal of the plate.

Figs. 4 and 5 are fragmentary horizontal sections illustrating twomodified embodiments of the catch attachment, respectively.

Figs. 6 and 7 illustrate a further modified catch as seen from onelateral face and from above, respectively.

Fig. 8 is a lateral elevation of a further modification of the catch.

Identical parts in the various representations have been allotted thesame reference numerals.

Referring now to the drawings, and more specifically to Fig. 1 thereof,a heat transferring ormatrix plate 1 has provided therein a slot 2embracing a carrier rod 01' bar 3 from which the plate is suspended bymeans of a catch 4 which at each end is attached to the plate on eitherside of the carrier bar. According to the present invention the catchconsists of two thin-gage sheet metal strips 5a and 5b, respectively,which are interconnected intermediate their ends, for instance by rivets6. Instead of being riveted together the strips could, for instance, bespot welded together. At their ends 7a, 7b and 3a, 81), respectively, atthe points of attachment the strips embrace an edge portion of the plateIt. In addition, each end of the strip 5b is provided with a hollow boss9a and 9b, respectively, made by stamping out material from the stripand adapted in the operative position of the catch to engagecorresponding holes it and ii in the plate 1 and in the other strip 5a,respectively. To remove the plate 1 from the carrier bar 3, as seen inFig. 3, the two strips are resiliently separated at one end of the catchso as to withdraw the boss 9a from the holes it) and 11 after which thecatch, being still in positive engagement with the plate 1 by its boss91;, is swung outwards pivoting about the latter boss into the positionindicated in broken lines in Fig. 1. Then the plate can be removed withthe catch still remaining connected thereto. Of course, it is possiblealternatively to release the catch at its boss 9b and then to swing itopen about the pivot boss 9a. In addition, the catch is readilyremovable completely from the plate 1, for replacement, for instance byreleasing the catch in the manner described at both ends. To mount theplate 1 on the carrier bar 3 again the catch is simply folded downcausing the relevant boss to snap into the corresponding hole in theplate, and a loose catch will be mounted in place therefore in acorresponding manner. The attachment legs, being of thin-gage sheetmetal, preferably of a thickness not exceeding 0.4 inch, can beresiliently spread apart manually without using any tool. Yet, theattachment will remain quite secure in the course of all kinds ofregular handling of the plate on its carrier bar since the spreadingmovement of the legs of the forked catch necessary for releasing theattachment cannot happen to be eiiected inadvertently.

Fig. 4 of the drawing illustrates a modified form of attachment in whichthe strip in of the catch has no holes provided therein for the bosseswhich latter will thus only engage the holes, respectively, made in theplate 1. This modified embodiment may be used to provide a cheaper catchin cases where the plates 1 have a comparatively small size and lightweight so that there will be no high requirement for the carryingstrength of the attachments. Particularly in such cases, and where, inaddition, the plates are very thin, the attachment may be still furthermodified according to Fig. 5 in which the plate 1 instead of the strip7b is provided with a hollow boss 90 adapted to engage a hole made insaid strip.

In cases where greater stress is laid upon the possibility of handlingthe plates with their catches remaining in situ, than upon the catchesbeing readily removable, for instance when transporting the plates toand from storage places for such plates, without the risk of the catchesgoing astray, it is possible by slightly upsetting one of the bosses ina rivet-like manner, such as shown at 12. in Fig. 3, to obtain thiseffect while maintaining the possibility of rotating the catch aboutthis pivot boss or rivet.

It will also be possible to give the catch a shape other than thestraight one exemplified in Fig. l, for instance an arcuate shapefitting onto the top portion of the carrier rod 3, thus enabling theslot 2 in the plate 1 to be made of less depth. Fig. 8 illustrates aconstructional form in which the catch 4a, in other respects shaped inthe man ner now described, is curved in a manner to enable said slot tobe omitted altogether. This involves a simplification of the plate 1, itbeing only necessary to provide the latter with the small holes 10 or,alternately, with bosses or projections 9c.

The punched-out or upset bosses as shown involve a particularly cheapand mechanically strong embodiment due to the fact that the elementsfrom which these bosses are to project consist of thin-gage sheet metal.

Figs. 6 and 7 of the drawing illustrate a modified form of the catch ofthe present invention. In this case the catch consists of an initiallyflat sheet metal blank having two oppositely disposed recesses or slots13a and 13b, respectively, aligned with each other and extending fromthe respective ends of the blank, after which the blank has been doubledalong the lateral edges of these recesses or slots so as to cause thelaterally spaced bent-over portions 50 and d to form stripscorresponding to the strips 5a and 5b, respectively, these strips thusbeing interconnected intermediate their ends through a back portion 14.The bosses 9a and 9b are suitably formed from the blank prior to thedoubling operation.

It should be understood that the embodiments hereinbefore described andillustrated in the accompanying drawing are to be considerd merely asgiven by way of example, and that persons skilled in the art guided bythese examples will be able to make further modifications thereofwithout departing from the scope of the invention.

What I claim is:

1. A heat exchanger of the plate-pile type comprising heat transferringplates of thin-gage sheet metal individually suspended from a carrierbar extending transversely to the faces of the plates, by means ofcatches individually provided one for each plate and extending acrossthe top portion of the carrier bar, each said catch being attached atits two ends on both sides of the bar to the corresponding plate, saidcatch being provided at both its ends with two resiliently separablelegs of thin-gage sheet metal adapted to grip an edge portion of theplate between their opposed fiat faces, each catch end being adapted toreleasably engage the plate only by resiliently spreading said legsapart.

2. A heat exchanger according to claim 1, wherein the portion of saidheat transferring plate disposed between said catch legs is providedwith a projection adapted to be passed through an opening in one of saidlegs, said legs being adapted, suitably manually and without using anytool, to be separated resiliently to an extent such as to cause saidopening in said leg to be disengaged by said projection.

3. A heat exchanger according to claim 1, wherein one of said legs isprovided with a projection directed towards the other leg and adapted tobe passed through a hole made in the portion of said heat transferringplate embraced by said legs which are adapted, suitably manually andwithout using any tool, to be spread apart resiliently to an extent suchas to cause said projection to be withdrawn from said hole in said heattransferring plate.

4. A heat exchanger according to claim 1, wherein one of said legs isprovided with a projection directed towards the other leg and adapted tobe passed through a hole made in the portion of said heat transferringplate embraced by said legs and through a hole made in the opposite leg,said legs being adapted, suitably manually and without using any tool,to be spread apart resiliently to an extent such as to cause saidprojection to be withdrawn from said hole in said opposite leg and fromsaid hole in said heat transferring plate.

References Cited in the file of this patent UNITED STATES PATENTS2,601,974 Hytte July 1, 1952

